Bonded joint or section of elastic fabric



Y 5- D. E. MORRISON ETAL I 2,380,365

BONDED JOINT OR SECTION OF ELASTIC FABRIC Filed June 12, 1940 PatentedJuly 10', 1945 BONDED JOINT OR SECTION OF ELASTIC FABRIC Dana E.Morrison, Kenilworth, and Paul .F. Ziegler, Winnctka, Ill., asslgnors toThe Kendall Company, Chicago, 111., a. corporation of MassachusettsApplication'June 12, 1940, Serial No. 340,008

14 Claims. 1 (Cl. 154-42) This inventionhas for its principal object theimprovement of joints between sections of garments in which one or moreof the sections to be joined is made of elastic fabric.

In the past, joints containing elastic fabric have usually been made bysewing or stitching (sometimes with the edge of the fabric doubled backso as to make the pulling out of the threads Such joints in athleticsupporters and other 5 more difficult) or by the use of metal clampselastic articles have presented a difficult problem of one form oranother. In the case of sewed in the past due largely to the changes incondijoints it has been the practice in some instances tion of theelastic fabric between its relaxed state to impregnate the area aroundthe joint with and its stretched state. The repeated stretchrubbersolutions or rubber latex with a view to ing and relaxing of the fabrichas caused the preventing the receding of broken or severed joint togive way before the garment was otherrubber threads. Sometimes thefabric has been wise worn out and has otherwise impaired the treatedbefore sewing and sometimes afterward, utility and durability .of thegarment, as will but in every instance of which we are aware the bebetter understood by considering the followstrength of the joint hasdepended upon the sewing description of structure of such fabric anding. The interstices of the fabric have been the changes in conditionwhich occur in normal only partially filled and the treated area hasusageremained to a. considerable extent elastic and The usual type ofelastic fabric comprises texsubject to the changing internal conditionsretile threads woven or knitted together, with sulting from stretchingand relaxing. The im rubber threads extending therethrough, therubpregnation has merely tied the rubber threads ber threads being.ordinarily covered by other more or less firmly to the textile threadsand textile threads wrapped or braided around the while this has tendedto delay the receding of same, although these covering threads may berubber threads due to the causes above-menomitted if desired. The exactstructure of the tioned, thus delaying the failure of the joint, itfabric and the method of fabricating it may of has not prevented theinternal changes which course vary according to the uses to which theultimately bring the failure. fabric is to be put and the particularcharac- Our invention provides a joint made without teristics desired.sewing or the use of metal clamps which effec- In the relaxed state thetextile threads or tively prevents the changes in condition of the yarnsand also the rubber threads are under fabric clue to stretching andrelaxing which have comparatively low tension; the fabric is thick beenthe principal cause of the dificulties preas comparedwith the stretchedstate and the viously experienced. degree of crimp in the threads,especially the While we have thus far referred only to joints, textilethreads, is high; the rubber threads are the invention from certainaspects is applicable large in cross section; the interstices betweenthe to portions of an elastic fabric which it is deinterlaced threadsare small; and relatively small sired to render immobile, i. e., notsubject to portions of the surfaces of the various threads stretch,whether the same enter into the joint are at the surface of the fabric.or not. In other words, there may be reasons In the stretched .statesubstantially the reverse other than the strengthening of a joint forimof the above conditions prevail, and in changmobilizing a section ofan elastic fabric, one ing from one condition to another there isrelaexample being shown in the accompanying drawtive movement betweenthe threads, with no ing, and the invention is to be regarded as apfixedrelation maintained "between the aboveplying to such a section as wellas to a joint. It described elements of the fabric. There is a tenisalso applicable to the formation of a stay to dency for the rubberthreads to retreat or move maintain the shape and to prevent the curlingthrough the fabric and the ends of such threads,v of a garment such, forexample, as a corset. unless effectively restrained, are likely to be inOther features of the invention and additional a different positionafter stretching of the fabric objects and advantages will be evidentfrom the than they were before. This may result from followingdescription and the accompanying pulling out of threads from the joint,which is drawing, in which: especially likely to occur if the joint isat an Fig. 1 is an elevational View of an athletic supangle or on a,curve, or from breaking of the porter in which the joint between thebelt and threads or severance of them by the needles of pouch, and alsocertain sections of-the belt, are a-sewing machine if the joint isformed by sewconstructed in accordance with my invention; g. 5 Fig. 2 isa plan view of a portion of the elastic Fig. 4 is a view similar to Fig.2- but showing the fabric in the relaxed state;

Fig. 5 is a sectional view taken substantially on the section line 5-5of Fig. 4;

Fig. 6 is a magnified and somewhat schematic view in cross section of ajoint made in accordance with my invention, the same being shown in therelaxed state of the fabric, and being taken substantially on thesection line H in Fig. 1;

Fig. 7 is a similar view of a portion of the joint, the same being shownin the stretched state of the fabric; and

Fig. 8 is a view similar to that of Fig. 6 but showing the parts in thestretched state of the fabric and omitting the facing strips on thesurfaces of the bonding material which are shown in Figs. 6 and 7.

The supporter shown in Fig. 1 of the drawing, as an illustration of oneembodiment of the invention, comprisesa belt 9, to the front portion ofwhich is attached a pouch ii, the lower end of which is connected tofront side portions oi the belt by means of leg hands it, the latterbeing sewed or otherwise suitably secured to said lower end of thepouch, as indicated at it], and to the belt at the points indicated bythe numerals M and 55, respectively.

The joint between the upper part of the pouch and the belt is indicatedgenerally in Fig. 1 by the reference numeral is d, as shown, isof inverted V-shape, with the lines of juncture exwnding diagonally acrossthe belt to substantially a point of convergence at the top. It will beunderstood that the invention is not restricted to this particularconfiguration or shape of joint, although it has special utility in connection with joints formed at angles or on curves since it overcomesdificulties especially experienced in connection with such joints, ashas been previously pointed out.

The construction of the joint is shown in detail in Figs. 6 to 8,inclusive, but before referring more particularly to these figures itisdesired to call attention to structural characteristics of the elasticfabric, as illustrated in Figs. 2 to 5, inclusive, it being understoodthat the pouch ii and the belt 9 in the present instance are both madeof elastic fabric. While the fabric of the pouch and that in the beltare difierent in specific form, both types of fabric contain rubberthreads and the general characteristics are suf-- ficiently indicatedfor present purposes in the above mentioned figures of the drawing. Itwill of course be understood that in some instances the joint may beused to connect a piece of elastic fabric to a piece of non-elasticfabric and the elastic fabric referred to herein may therefore beregarded as one or more of the materials entering into the joint.

In said Figs. 2 to 5 of the drawing, the rubber threads are indicated bythe numeral ll, the

accuses v state as shown in Figs. 2 and 8, and the relaxed from Figs. 2and 4. Furthermore, the change textile threads extending in directionparallel to said rubber threads by the numeral 98, and the textilethreads extending indirection at right angles to the above meutionedthreads by the numeral it. Said threads are interlaced to form in thepresent instance what is sometimes referred to as a "basket weave," andit will be observed that there is a very decided change in condition ofthe fabric between the stretched in relationship of the textile threadsto each other as well as to the rubber threads, as ,between thestretched and relaxed states of the fabric, is clearly illustrated inthese figures and in Figs. 3 and 5. The covering of textile threads onthe individual. rubber threads is not shown in Figs. 2 to 5, but isshown in Figs. 6 to 8, wherein said threads, which are wrapped spirallyaround the rubber threads, are indicated by the numeral El.

The joint it comprises a bonding material 22 shown in Figs. 6 to 8 ofthe drawing and prefer-' ably also fabric facing strips 23 on one orboth sides of thejoint, such strips being shown in Figs. 6 and '7 butnot in Fig. 8. The bonding material may be chosen from thermoplasticmaterials which are solid at ordinary temperatures and retain theirthermoplastic. properties after the temperature and pressure' treatmentused to form the joint, but is preferably chosen from materials whichlose their plasticity after such treatment, such materials beingcommonly de scribed as thermosetting materials. Examples of the formertype of materials are unvulcan ized rubber, cellulose esters and others,vinyl and acrylic resins; examples of the latter are vulcauizablerubber, phenolfcrmaldehyde plastics and urea formaldehyde plastics. Theproper degree of flexibility of the bonding material to meet theparticular requirements of a joint can be obtained through plasticizerformulation. Said bonding material fills practically all of theinterstices of the fabric in the area to which it is applied and adheresto practically all of the threads in the fabric. When the joint is abutt joint, 1. e., one in which the fabric pieces do not overlap but arearranged edge to edge, said mbterial fills the space between said edges,as indicated at 24 in the drawing, forming a link-between the two piecesof fabric. In this regard it is also advantageous to select a bondingmaterial which will firmly adhere to the end portions of the rubberstrands, to further prevent them from being pulled out of the joint byrepeated tension, although ordinarily the degree of com pressionon thetextile threads along the length of rubber threads within the jointeasily fulfills this requirement.

The bonding material may be applied by plac= ing a strip thereof overthe area to be bonded and applying heat and pressure thereto, preferablyin a. confined space, the material becoming plastic at a temperaturelower than the scorch point of the fabric and being caused to flow intothe interstices of the fabric so as to complete-h or substantially fillthe same and to form a solid and substantially inelastic section ormatrix indefinitely confined area and a solid link will be formedbetween the edges of the fabric at the point indicated by the numeral24. result in preventing changes in the internal condition of the fabricin the area of the joint, and will form a secure and durable jointwithout the use of stitching, metal clamps, or any means other than thebonding material itself.

Furthermore, it is possible to obtain an immobilized section of elasticfabric in desired form preferably made of non-elastic fabric and serve.

to further immobilize the bonded area as well as to provide a smoothsurface, which is desirable in garments such as the one shown in Fig. lof the drawing. Furthermore, the use of such reinforcing strips allows amore varied selection of bonding materials than would otherwise befeasible, since not only can materials with surfaces which wouldotherwise be too rough for- This will garments of this character beused, but mate- I rials with more elasticity and plasticity and lesstensile strength and tear resistance can be employed without impairingthe strength of the joint, as the reinforcing strips can take over partof the load on the joint and help t prevent stretch of the fabric in thearea covered thereby.

It will be noted from Figs. 6 to 8 that the thickness of the fabric inthe areaof the joint is not increased, and, in fact, by application ofsufficient pressure, it is possible to even slightly decrease thethickness at this point if it should be desired to do so.

It will be observed by comparison of Figs. 6 and 7 .that when the fabricis stretched, the rubber threads I! and the textile threads, of whichonly the threads I! are shown in these figures,

are elongated and separated in the area adiacent that to which thebonding material has been applied but are unafi'ected in the latterarea. There is practically no stretch in the bonded section, andnochanges in condition. of the fabric occur which would tend to loosenthe rubber threads from the textile threads and cause them to recedefrom the point of juncture and thus weaken the Joint, as has been thecase with former constructions. Instead of being the weakest point inthe garment, as in former constructions, the joint becomes the strongestpoint, and holds firmly even though the joint may be on a curve or at anangle.

When one or both of the facing strips areomitted, there may be a slightstretch in the bonding material, as evidenced by some contractionthereof near the edges of the bonded section as shown in Fig. 8. buteven in this form of th Joint the area near the edges of the fabric andin the link 24 between said edges, is practically non-elastic and servesto immobilize the portions of the elastic fabric where failure has'usually occurred in prior constructions.

As has been previously mentioned, the principles of the invention may beapplied for the purpose of immobilizing a section of an elastic fabricelsewhere than in the vicinity of a joint, and in Fig. 1 of the drawingwe have shown,'in opposite sides of the belt near the points where theleg bands are attached, sections 25 treated substantially as has beendescribed with reference to the joint 18. These sections serve toprevent undue stretching of the belt in the vicinity of the points ofattachment of the leg bands and tend to maintain a hired right-anglerelationship between the belt and the ends of the bands so as to preventundue strain at the point of at-- tachment. It will be understood thatthese treated sections may or may not be employed in the supporter, butfrom certain standpoints they are advantageous, and they are an exampleof the application of the principles of the invention to a section ofthe fabric where there is no joint.

- Furthermore, the invention, as hereinbefore indicated, is applicablein forming lap joints or in joining pieces of fabric elsewhere than atthe edges thereof, the form of joint illustrated be ing only one exampleof the various forms which may be made by the mechanism described.

For-the sake of simplicity and because such fabrics are commonly used,we have shown in the detailed views of the drawing an elastic,

fabric which is stretchable in only one direction, namely that in whichthe threads l1 extend. However, elastic fabrics which are stretchable intwo directions are also in common use, a specific example being that ofthe pouch material II shown roughly in Fig. 1, and the invention mayalso be utilized with such two-way stretch material, its advantages inthis case being even greater than with the material specificallyillustrated, since still more severe requirements are imposed on thejoint when the material stretches in two directions insteadof only one.

The foregoing detailed description has been given for cleamess ofillustration only, and no' unnecessary limitations should be understoodtherefrom, but the appended claims should be construed as broadly aspermissible in view of the prior art.

We claim:

1. An elastic fabric having a section in which the elastic properties ofthe fabric have been practically nullified and the possibility ofinternal changes in the relationship of the threads has been practicallyeliminated by reason of the presence in said section of a thermosettingbonding material which is plastic at a temperature below the scorchpoint of the fabric but is solid at normal atmospheric temperatures andwhich fills substantially all the interstices and adheres tosubstantially .all the threads of the fabric in said section. I

2. An elastic fabric having a section inwhich the elastic properties ofthe fabric have been practically nullified and the possibility ofinternal changes in the relationship of the threads has been-practicallyeliminated by reason of the presence in said section of a thermosettingbonding material which is plastic at a temperature below the scorchpoint of the fabric but is solid at normal atmospheric temperatures andwhich fills substantially all the interstices and adheres tosubstantially all the threads of the fabric in said section, saidsection being nevertheless flexible and being moulded to a desiredshape. 1

3. An-elastic fabric having a section in which the elastic properties ofthe fabric have been practically nullified and the'possibility ofinterhe] changes in the relationship of the threads has been practicallyeliminated by reason of the presence in said section of a thermosettingbond.- ing material which is plastic at a temperature below the scorchpoint of the fabric but is solid at ricrmal'atmospheric temperatures andwhich fills substantially all the interstices and adheres tosubstantially all the threads of the fabric in said section, saidsection having therein a, reinforcing strip of non-elastic materialadhering to said bonding material.

4. A garment comprising two or more pieces of material one or more ofwhich is an elastic fabric, and means forming a bonded joint between twopieces of said material at least one of which is elastic fabric, saidmeans comprising a thermosetting bonding material connecting said twopieces and filling substantially all the interstices of a portion of theelastic fabric adjacent the point of connection and rendering saidportion substantially non-elastic and free from internal changes such asnormally occur in elastic fabric in the stretching and relaxing thereof.

5. A garment comprising two or more pieces of material one or more ofwhich is an elastic fabric, and means forming a bonded joint between twopieces of said material at least one of which is elastic fabric, saidmeans comprising a thermosetting ,bonding material connecting said twopieces and filling substantially all-the interstices of a portion of theelastic adjacent the point of connection and rendering said portionsubstantially non-elastic and free from internal changes such asnormally occur in elastic fabric in the stretching and relaxing thereof,and a reinforcing strip of non-elastic material adhe to said bondingmaterial.

6. A garment including sections one .or more of which is made of elasticfabric, said elastic fabric comprising non-elastic textile threads andelastic rubber threads arranged among said nonelastic threads to form,in combination with said textile threads, 8. highly porous, extensiblestructure with interstices therein, a, joint between sections of saidgarment including a section of said elastic fabric, said jointcomprising an impregnation of rubber substantially completely fillingthe interstices of said porous fabric in the area at the joint, therebyfilling the fabric at least the matrix are practically destroyed and.rendered inoperative.

7. A garment including sections one or more which is made of elasticfabric, said elastic fabric comprising non-elastic textile threads andelastic rubber threads arranged among said nonelasticthreads to form, incombination with said textile threads, 'ahighly porous,extensiblestructure with interstices therein, and a joint betweensectionsof said garment including a. section of said elastic fabric,said joint comprising an impregnation of rubber substantially completelyfilling the interstices of said porous fabric in the area at the joint,thereby filling the fabric at least fromthe center to the outermostthreads of the elastic fabric in a matrix of rubber, and a. strong linkof rubber integral with said matrix located between juxtaposed portionsof the garment, said unital matrix and link forming a strong,self-sumcient and substantially non-elastic joint in which theextensible properties of the elastic fabric within the matrix arepractically destroyed and rendered inoperative.

8. A garment including sections one or more of which is made of elasticfabric, said elastic fabric comprising non-elastic textile threads andelastic rubber threads arranged among said nonelastic threads to form,in combination with said textile threads; a highly porous, extensiblestructure with interstices therein, and a joint between sections of saidgarment including a section of said elastic fabric, said jointcomprising an impregnation of thermosetting bonding materialsubstantially completely filling the interstices of said porous fabricin the area at the joint, thereby filling the fabric at least from thecenter to the outermost threads of the elastic fabric in a matrix ofsaid bonding material, and a strong link .of said bonding materialintegral with said matrix located between juxtaposed portions of thegarment, said unital 'matrix and link forming a strong, self-sufficientand substantially non-elastic joint in which the extensible propertiesof the elastic fabric within the matrix are practically destroyed andrendered inoperative.

9. An elastic fabric having a section in which the elastic properties ofthe fabric have been practically nullified and the possibility ofinternal changes in the relationship of the threads has been practicallyeliminated by reason of the presence in said section of a thermosettingbonding material which fills substantially all the interstices andadheres to substantiallyall the threads of the fabric in said section.

10. A garment comprising two or more pieces of material one or more ofwhich is an elastic fabric, and means forming a bonded joint between twopieces 'of said material at least one the elastic properties of thefabric have been practically nullified and the possibility of in-'-ternal changes in the relationship of the threads has been practicallyeliminated by reason of the presence in said section of a bondingmaterial comprising vulcanized rubber which fills substantially .all theinterstices and adheres to substantially all the threads of the fabricin said section.

j 12. A garment comprising two or more pieces of material one or more ofwhich is an elastic fabric, and means forming a bonded joint between twopieces of said material at least one of which is elastic fabric, saidmeans comprising a. bonding material of vulcanized rubber connectingsaid two pieces and filling substantially all the interstices ofa-portion of the elastic fabric'adjacent the point of connection andrendering said portion substantially non-elastic and free from internalchanges such as normally ocour in elastic fabric in the stretching andrelaxing thereof.

13. A garment comprising two or more pieces of material one or more ofwhich is an elastic fabric, and means forming a bonded joint between twopieces 'of said material at least one of which is elastic fabric, saidmeans comprising a thermosettingbonding material connecting said twopieces and filling substantially all the interstices of a portion of theelastic adjacent the point of connection and rendering said portionsubstantially non-elastic and free from incf materialone or more ofwhich is an elastic temal changes such as normally occur in elas- 14. Agarment comprising two or more pieces fabric, means forming a bondedjoint between two pieces of said-material at least one of which iselastic fabric, said means comprising a thermosetting bonding materialconnecting said two pieces and filling substantially all the intersticesof a portion of the elastic adjacent the point of connection andrendering said portion substantially non-elastic and free from internalchanges such as normally occur in elastic fabric in the stretching andrelaxing thereof, said bonding material being applied on both sides ofthe elastic fabric and filling the interstices in said portion thereofthroughout the entire thickness of the fabric to thereby immobilize thethreads in said portion and thus prevent relative movement thereof, andreinforcing strips of non-elastic material bonded to said bondingmaterial on both sides of the fabric.

DANA E. MORRISON.

' PAUL F. ZIEGLER.

